KIE: The fourth congress of International Physicians for the Prevention of Nuclear War, attended by over 400 physicians from 50 countries, focused on the psychological impact of the nuclear threat, the economic effects of the arms race on international health care, and the global ecological effects of a major nuclear exchange. A report to the congress noted that over a million signatures of physicians have been gathered in response to an appeal, the "International Physicians' ¿Call for an End to the Nuclear Arms Race." The conference agreed upon the text of a letter, to be distributed to patients by doctors, which describes medical concerns about nuclear war.